Nonequilibrium relaxation of soft responsive colloids

Year: 2024

Type: article

Abstract: Stimuli-responsive macromolecules display large conformational changes during their dynamics, sometimes switching between states. Such a multi-stability is useful for the development of soft functional materials. Here, we introduce a mean-field dynamical density functional theory for a model of responsive colloids to study the nonequilibrium dynamics of a colloidal dispersion in time-dependent external fields, with a focus on the coupling of translational and conformational dynamics during their relaxation. Specifically, we consider soft Gaussian particles with a bimodal size distribution between two confining walls with time-dependent (switching-on and off) external gravitational and osmotic fields. We find a rich relaxation behavior of the systems in excellent agreement with particle-based Brownian dynamics computer simulations. In particular, we find time-asymmetric relaxations of integrated observables (wall pressures, mean size, and liquid center-of-mass) for activation/deactivation of external potentials, respectively, which are tunable by the ratio of translational and conformational diffusion time scales. Our work thus paves the way for studying the nonequilibrium relaxation dynamics of complex soft matter with multiple degrees of freedom and hierarchical relaxations.

Source: The Journal of Chemical Physics

DOI: 10.1063/5.0221903

Authors: José López-Molina, Sebastien Groh, Joachim Dzubiella, Arturo Moncho-Jordá

Institutions: Universidad de Granada, University of Freiburg

Language: English

Topic: Material Dynamics and Properties

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,500

Funders: Deutsche Forschungsgemeinschaft, Ministerio de Ciencia e Innovación, Universidad de Granada, European Regional Development Fund, Agencia Estatal de Investigación, Ministerio de Universidades

OpenAlex ID: W4402207233